1. Field of the Invention
The present invention relates to an absorbent article having a surface layer, in which a porous film and a fibrous layer are combined, for increasing the wearer""s comfort during wear.
2. Description of the Related Art
Absorbent articles, such as sanitary napkin, disposable diaper or the like are typically of construction in which an absorbent layer is laid over a liquid impermeable backing sheet, and a liquid permeable surface material is laid over the liquid receiving side of the absorbent layer.
As the surface material, it is known in the art to use a synthetic resin film sheet formed with a large number of through holes. In this film sheet, the large number of through holes function as courses or ducts for permitting passage of liquid. Therefore, the liquid applied to the sheet surface is permitted to pass through the holes to be absorbed in the absorbent layer. Hereinafter, such a film with holes is referred to as a porous film.
This porous film sheet never exhibits capillary action for retaining liquid around the through holes, unlike a non-woven fabric made of fiber aggregate. Therefore, the liquid applied to the film sheet surface can be easily guided to flow into the through holes. In addition, by adding inorganic filler into the film sheet for whitening, the film sheet can conceal the menstrual blood or the like absorbed in the absorbent layer through the through holes.
However, the porous film sheet is liable to stick to the skin of a wearer. Therefore, it hardly follows motion of the wearer""s skin to thereby possibly provide irritation to the skin. In addition, the porous film sheet is inferior in the function of pulling (attracting) fine drops of liquid from the wearer""s skin to the sheet, as compared with a non-woven fabric. As a result, it is liable to provide wet feeling to the wearer""s skin.
On the other hand, also known are a sheet in which a resin layer is formed into strips on the surface of the porous film sheet, and a sheet in which a thin non-woven fabric is laid over the entire surface of the porous film sheet. These sheets are intended to make advantage of the merits of the porous film sheet.
However, although the former can reduce the contact area with the wearer""s skin, it still remains difficult to follow motion of the wearer""s skin. Therefore, it is difficult to prevent irritation to the skin. On the other hand, although the latter can provide soft contact feeling to the wearer""s skin, the non-woven fabric is liable to retain liquid by capillary action of fibers forming the non-woven fabric. Therefore, it is liable to provide wet feeling to the wearer""s skin.
The present invention has been worked out in view of the shortcoming in the prior art set forth above. It is therefore an object of the present invention to provide an absorbent article which makes merit of a porous film, provides soft contact feeling to the skin of a wearer, and hardly causes retention of fluid.
According to the invention, there is provided an absorbent article comprising: a liquid permeable surface layer; a backing sheet; and an absorbent layer interposed between the surface layer and the backing sheet, the surface layer including: a porous film having a plurality of through holes; and a fibrous layer disposed on the liquid-receiving face of the porous film, the fibrous layer being of a plurality of strips extending in parallel and spaced apart from each other, each strip of the fibrous layer being fixed to the porous film at spaced fixing portions, so that the porous film is exposed between adjacent strips of the fibrous layer.
The absorbent article according to the present invention can easily guide the liquid to the absorbent layer through the holes in the porous film. With the strips of the fibrous layer, moreover, the absorbent article can provides soft contact feeling to the skin of a wearer. Since fibers appearing on the surface of the fibrous layer can follow motion of the skin of a wearer, still moreover, irritation to the wearer""s skin can be reduced.
Preferably, the fixing portions are spaced apart from each other in a direction along which the strips of the fibrous layer extend, and each strip is raised between adjacent fixing portions away from the porous film, to form a plurality of loop portions. In this construction, fibers on the surfaces of the loop portions can easily move in any directions to follow motion of the skin of a wearer. Moreover, the liquid can flow down along the slope of the loop portion toward the porous film so that the liquid can be easily guided to the through holes.
For example, the porous film may be contracted in the direction along which the strips of the fibrous layer extend, after the strips are fixed to the porous film, for reducing the pitch between adjacent fixing portions for raising the loop portions. In this construction, the porous film may be formed of a stretchable synthetic resin film. In an alternative, the absorbent article may further comprise an elastic member fixed on the porous film, for providing contracting force to the porous film. In another alternative, the porous film may be formed of a heat-shrinkable synthetic resin film. In the case where the porous film is formed of the stretchable synthetic resin film, it is preferred that the through holes are opened in a quadrangular shape, so that the porous film is formed with separation strips separating adjacent quadrangular through holes, the separation strips extending oblique relative to the direction along which the strips of the fibrous layer extend.
Preferably, a total length L along the outermost surface of each loop portion, between adjacent fixing portions, is in a range of 1.1 to 4 times of a pitch P between adjacent fixing portions.
For example, the fibrous layer may be formed of a bundle of continuous filaments. Alternatively, the fibrous layer may be formed of a non-woven fabric. In this case, it is preferred that each strip of the fibrous layer is formed of a bundle of thin strips formed by cutting the non-woven fabric.